>>2575291. Myu can tell her, "Hey, I don't think I can do this, I'm finally getting to where I want to be and it's just too much for me to go back now." Quick, simple, sets up boundaries, and ultimately, since Nadette already said she'd understand if Myu refused, then if had a problem with it, it would be on her, not Myu.
2. Zina moved out over boundaries. Either she'd understand or she'd get over it.
3. She recognized multiple times that she was gaining weight, so it can't just be about maintaining. You can make the claim that she overshot her mark on what she actually ended up gaining, but considering her response to Zina mentioning it was essentially: "Meh. I can do what I want because Nadette has no other options" is pretty shitty either way.
4. She was already overeating before she saw the linker, so that's a poor justification, whether it's true or not.
5. I won't call it a full betrayal, but ultimately, Myu agreed to help Nadette, had the awareness to recognize that she had her friend over a barrel, and decided that meant she could do whatever suited her regardless of any assurances she made to Nadette. By doing it that way, instead if just telling Nadette she couldn't do it, Myu likely wasted time that Nadette could have used to focus on finding a suitable entourage, (or at least someone at the bottom of the barrel).
6. That's a good point that coiukd have been brought up WHEN NADETTE ASKED HER IN THE FIRST PLACE, instead of leading her on about something that Myu knew was important to her and still brushed off.